基于Backstepping方法的车式移动机器人轨迹追踪控制

Tracking control of car-like mobile robot based on Backstepping

针对四轮车式移动机器人的运动学模型,首先利用一个正则坐标变换,将误差系统转换为一个非线性串联系统的形式;然后利用Backstepping方法,在两轮移动机器人追踪控制律设计过程的基础上,构造了四轮移动机器人追踪系统的Lyapunov函数,并通过使该Lyapunov函数负定,计算得到了针对四轮移动机器人轨迹追踪控制器,并证明了该类型移动机器人在所得控制器作用下,能实现对给定目标的全局渐近追踪;最后利用提出的控制器,通过四轮移动机器人对直线和圆周 2种轨迹追踪的仿真实验,验证了该控制器在四轮车式移动机器人轨迹追踪控制中的有效性.

Aimed at the kinematic model of the car-like mobile robot with four wheels, the tracking error system is firstly transformed to a nonlinear serial system through a regular transformation. Through the Backstepping method, the Lyapunov function of the car-like mobile robot with four wheels is then constructed based on the design procedure of the trajectory tracking controller of two wheel mobile robot, and the tracking controller of car-like mobile robot with four wheels is proposed in order to make the constructed Lyapunov function negative. It is proved that this kind of robot can globally asymptotically track a given target under the proposed controller. Finally, the effectiveness of the proposed controller is shown through the simulation of car-like mobile robot tracking line and circle trajectory under the proposed controller.